[Solved]-Using Django bulk_create objects in foreign keys?

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6đź‘Ť

Try setting the ids manually. To prevent race conditions, make sure to wrap the function as a single transaction.

from django.db import transaction, models

@transaction.commit_on_success
def bulk_create_with_manual_ids(foo_list):
    id_start = (Foo.objects.all().aggregate(models.Max('id'))['id__max'] or 0) + 1
    for i,foo in enumerate(foo_list): foo.id = id_start + i
    return Foo.objects.bulk_create(foo_list)

objList = [Foo(),Foo(),Foo()]
foo_objects = bulk_create_with_manual_ids(objList)
Bar(foo=foo_objects[0]).save()

Note that this approach is unsuitable for any table that has a serial field or other auto-incrementing in-database generated key. The key will not be incremented by the bulk create since IDs are being generated on the Django side.

👤egafni

3đź‘Ť

For the first question, no you won’t be able to do that, because obj won’t have its primary key set so couldn’t be used as a foreign key.

The second question, no that’s not what it says at all. It specifically mentions “multi-table inheritance”: inheriting from an abstract model is not multi-table inheritance.

👤Daniel Roseman

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